With the further development of mobile terminal device, there are a wide range of universal terminal equipments available in the market, such as a GSM terminal, a CDMA terminal, a WCDMA terminal, and a dual-mode and multi-standby terminal. At the same time, some trunking systems and terminals thereof directed to particular users have been developed and applied quickly, for example, a CDMA-based trunking system, gota. The trunking-based terminal equipment is important in the mobile terminal market. Generally, a trunking terminal is directed to users in a specific field, such as dockworkers, taxi drivers, traffic police, etc. However, the existing trunking system and the terminal thereof have some problems in certain aspects, for instance, a registration problem is widely existed in a current terminal of trunking function based on CDMA wherein if a incoming call is received before the PTT terminal registration, the trunking terminal can not carry out the registration or the registration is abnormal, thus resulting in terminal malfunctions.